In the beginning of creation Brahma created not only saintly sons but also demonic offspring.
It is understood herein that Adharma, Irreligion, was also a son of Brahma, and he married his sister Mrsa. This is the beginning of sex life between brother and sister. This unnatural combination of sex life can be possible in human society only where there is Adharma or Irreligion. It is understood that in the beginning of creation Brahma created not only saintly sons like Sanaka, Sanatana and Narada but also demonic offspring like Nirrti, Adharma, Dambha, and Falsity. Everything was created by Brahma in the beginning. Regarding Narada, it is understood that because his previous life was very pious and his association very good, he was born as Narada. Others were also born in their own capacities, according to their backgrounds. The law of karma continues birth after birth, and when there is a new creation, the same karma comes back with the living entities. They are born in different capacities according to karma even though their father is originally Brahma, who is the exalted qualitative incarnation of the Supreme Personality of Godhead.
From Dambha and Maya were born Greed and Nikrti, or Cunning. From their combination came children named Krodha (Anger) and Himsa (Envy), and from their combination were born Kali and his sister Durukti (Harsh Speech). By the combination of Kali and Harsh Speech were born children named Mrtyu (Death) and Bhiti (Fear). From the combination of Mrtyu and Bhiti came children named Yatana (Excessive Pain) and Niraya (Hell).
The creation takes place on the basis of goodness, but devastation takes place because of irreligion. That is the way of material creation and devastation. Here it is stated that the cause of devastation is Adharma or Irreligion. The descendants of Irreligion and Falsity, born one after another, are Bluffing, Cheating, Greed, Cunning, Anger, Envy, Quarrel, Harsh Speech, Death, Fear, Severe Pain, and Hell. All these descendants are described as signs of devastation. If a person is pious and hears about these causes of devastation, he will feel hatred for all these, and that will cause his advancement in a life of piety. Piety refers to the process of cleansing the heart. As recommended by Lord Chaitanya, one has to cleanse the dust from the mirror of the mind, and the advancement on the path of liberation begins. Here also the same process is recommended. Malam means: “contamination.” We should learn to despise all the causes of devastation, beginning from irreligion and cheating, and then we shall be able to make advancement in a life of piety. The possibility of our attaining Krishna consciousness will be easier, and we shall not be subjected to repeated devastation. The present life is repeated birth and death, but if we seek the path of liberation, we may be saved from repeated suffering.
Source: A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “Srimad Bhagavatam”, Fourth Canto, Chapter 08 – Text 02 to 05